While I like the LoS markers in theory I’m not liking the current implementation, solely because I have a lot of trouble seeing the lines.
I suspect this is purely a problem with my colourblindness, but it is still an issue. Several times I gone to a square I though had LoS, but didn’t because I’ve lost sight of the LoS lines.
Hmm, yeah, any game worth it’s salt has colour blind options. I’m sure these are already being considered but it doesn’t hurt to request them either. 
On another note about Line of Sight lines: Often your soldiers have a good shot on an enemy behind cover but this is never seen unless you manually look around with the first person view. What I mean by this is that if there’s an enemy standing behind a weak wooden box then your soldier can shoot, breaking the box and then damaging the enemy with the remaining 5 bullets (assuming assault trooper). Similarly with the sniper rifle, i’m fairly sure it can straight up shoot right through certain pieces of cover, although I might have just gotten extremely lucky and ‘threaded the needle’ on that one… (sniper rifles should be able to shoot through most cover since it has armour piercing anyway.)
So I would like to see an extension to the line of sight where it shows a yellow line for enemies behind cover but still vulnerable to fire. Perhaps even a grey line, swapping with the ‘out of AP’ line.
I think it works fine, you see a red laser sight pointing towards the enemy. It’s a flash, but it’s hard to miss.
it is very easy to miss if you have a red deficiency or are completely red blind.
I like the idea and implementation and found myself using it to help determine where soldiers should move to. I think colour blind options should be added to make this clearer for those who need it.